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Attraverso uno studio di caso, centrato su Marie-Anne Paulze-Lavoisier (1758-1836), la tesi tratta di pratiche legate all’annotazione e, più in generale, alla registrazione di informazioni su supporti cartacei tra gli anni ’70 del Settecento e gli anni ‘30 dell’Ottocento. Nota oggi come moglie e collaboratrice del chimico Antoine-Laurent Lavoisier (1743-1794), di cui avrebbe promosso le teorie attraverso un’attività di traduttrice e illustratrice, Paulze-Lavoisier è qui presentata nella veste di “secrétaire”, ossia di figura incaricata di mettere per iscritto osservazioni di varia natura. Ci si concentra, in particolare, sui Registres de laboratoire di Lavoisier, 14 quaderni petit in-folio a cui sono affidati i resoconti di esperimenti condotti a Parigi tra il 1772 e il 1788 e che rilevano in misura significativa della mano di lei. Oggetto finora di una storia del pensiero scientifico, interessata alle “idee” in essi contenute, i Registres sono da noi riletti alla luce di un approccio “materiale”, attento alle pratiche e alle condizioni della loro compilazione e del loro riutilizzo nel tempo. Si indagano quindi le funzioni di questi quaderni rispetto alla pratica sperimentale, ricostruendo al contempo i tratti e le evoluzioni del ruolo di segretaria affidato a Paulze-Lavoisier. Il focus su Paulze-Lavoisier permette da un lato a sollevare nuove domande in merito al rapporto tra scrittura delle note, genere e sociabilità ma anche, ad un altro livello, alla cosiddetta “invisibilità” degli assistenti; dall’altro offre la materia per una storia lunga dei Registres, che dai primi gesti in essi da lei operati agli inizi degli anni ’70 del Settecento arriva fino alle manipolazioni a cui sono sottoposti, per sua volontà, nei primi decenni dell’Ottocento., Taking Marie-Anne Paulze-Lavoisier (1758-1836) as a primary case study, this dissertation examines note-taking practices and information management during the long eighteenth-century (1770-1830 circa). Known as the wife and scientific associate of the French chemist Antoine-Laurent Lavoisier (1743-1794), and more notably, as a translator and illustrator of chemical texts on her own right, Paulze-Lavoisier is here presented as a secretaire and namely as someone whose main charge was to store and exchange information by means of writing. I focus, in particular, on the so-called Registres de laboratoire: 14 notebooks containing the accounts of numerous experiments performed by Lavoisier and his associates in Paris between 1772 and 1788 and annotated thoroughly by Paulze-Lavoisier. In contrast to previous historiography, I reassess the meaning of the Registres in the light of the practices by which they were compiled, consulted, and preserved. By tracing Paulze-Lavoisier’s interventions and exploring the material and social conditions in which they were made, I show the role of scribal practices in Lavoisier’s working routine and, at the same time, I retrace her trajectories as a secrétaire. In the last part of the dissertation, I explore the fate of the Registres after Lavoisier’s death in 1794, when Paulze-Lavoisier’s work as a secrétaire took new directions. The broader aim of the thesis is to raise new questions relating to the relationships between note-taking practices, gender, and sociability as well as to the social construction of scientific authority, and the social visibility of scribal helpers and assistants before and after the French Revolution.

L'articolo esplora i primi cento anni di storia dell'Accademia pistoiese di Scienze, Lettere ed Arti (1743-1848, esaminando l'attività scientifica portata avanti dai suoi membri. Facendo uso di documenti inediti, si ricostruiscono alcuni dei dibattiti di maggiore rilevanza animati in seno all'istituzione e relativi, soprattutto, alle evoluzioni della chimica di fine Settecento.

Environmental status and conservation values of Croatian rivers have never been comprehensively assessed. We present a methodology for the identification of the most pristine rivers of high conservation value which are important for the protection of freshwater biodiversity in Croatia. The methodology is a combination of ecoregional conservation approach where representation of all distinct biodiversity features is a key goal, and assessment of river reach condition. Main units of analysis, the Evaluated River Reaches (ERRs), were identified after all river types were distinguished. The condition of each ERR was assessed using a combination of five criteria: hydrology, channel morphology, riparian vegetation, water quality and land use. The final condition of ERR was scored (max. 50) by summing scores for the five criteria. The distribution of endangered freshwater f ish species and protected areas was used for prioritizing the ERRs in high and good condition. Altogether 82 rivers and 4522 km of river length were analyzed in three ecoregions: Pannonian, Dinaric‐Continental and Dinaric‐ Mediterranean. The total length of very high priority ERRs was 1607 km (35%), while additional ERRs comprising 998 km (22%) of river length were included to assure representation of all river types in each ecoregion. The selected ERRs represent priority river reaches whose protection should ensure the long term persistence of the most important features of freshwater biodiversity in Croatia.

This paper reports on DNA DSB induction in human fibroblasts by iron ions of different energies, namely 5, 1 GeV/u, 414 and 115 MeV/u, in absence or presence of different shields (PMMA, Al and Pb). Measure of DNA DSB was performed by calibrated Pulsed Field Gel Electrophoresis using the fragment counting method. The RBE–LET relationships for unshielded and shielded beams were obtained both in terms of dose average LET and of track average LET. Weak dependence on these parameters was observed for DSB induction. The shielding efficiency, evaluated by the ratio between the cross sections for unshielded and shielded beams, depends not only on the shield type and thickness, but also on the beam energy. Protection is only observed at high iron ions energy, especially at 5 GeV/u, where PMMA shield gives higher protection compared to Al or Pb shields of the same thickness expressed in g/cm2.

Taking risks is a natural human response, but, in some, risk taking is compulsive and may be detrimental. The subthalamic nucleus (STN) is thought to play a large role in our ability to inhibit responses. Differences between individuals' ability to inhibit inappropriate responses may underlie both the normal variation in trait impulsivity in the healthy population, as well as the pathological compulsions experienced by those with impulse control disorders (ICDs). Thus, we review the role of the STN in response inhibition, with a particular focus on studies employing imaging methodology. We also review the latest evidence that disruption of the function of the STN by deep brain stimulation in patients with Parkinson's disease can increase impulsivity.

12th International Congress of Radiation Research

Protons and high energy heavy ions (HZE particles ) are the components of space radiation of major concern. Their biological consequences are expected to be related to DNA lesions. Since DNA double strand breaks (DSB) and other lesions produced by these charged particles occurs in a correlated manner along the particle track, the current working hypothesis is that spatial correlation of damage, that depends on the particle type and energy, affects its reparability. Several characteristic distances for damage correlation can be considered, related to various levels of chromatin organization. We have investigated, in AG1522 human fibroblasts, the DNA fragmentation patterns in the size range 23 kbp - 5.7 Mbp, characteristic of the loop structure of chromosomes, using calibrated Pulsed Field Gel electrophoresis (PFGE). We have compared various beams i.e., low -energy protons of 0.88 MeV (representative of stopping protons at the Bragg peak) and Fe ions of 1050 and 414 MeV/u, using g-rays as reference. Irradiations with protons were performed at the Laboratori Naz ionali di Legnaro (Padova, Italy), those with 1050 MeV/u Fe ions at the Brookhaven National Laboratory (USA) and those with 414 MeV/u Fe ions at the National Institute for Radiological Sciences (Chiba, Japan). DSB yields were evaluated from the number of DNA fragments induced in the size range studied, at doses between 40 and 200 Gy. The results until now obtained show the general trend of a linear, or almost linear, increase of DSB with the dose. 1050 MeV/u Fe ions are the most effective particles in terms of both unit dose and unit fluence. The frequency distributions of fragments induced by the charged particles are shifted towards smaller sizes with respect to that induced by comparable doses of g-rays. These distributions also suggest that at doses of the order of 100 Gy most of the fragments induced by protons have size > 23 kbp, while for Fe ions it is expected a significant amount of fragments smaller than that size, not revealed by the mentioned PFGE analysis. This is in agreement with recent experimental measurements of DNA fragments induced by 1050 MeV/u Fe ions in the size range 2 - 23 kbp. The occurrence of such small fragments (and even smaller) further increases the effectiveness for DSB induction of HZE particles compared to protons., 34th COSPAR Scientific Assembly

The 2nd International Workshop on Space Radiation Research

There is a strong need for radiobiological experiments on carbon ions, to better determine the biological effectiveness as a function of radiation quality and to optimise the clinical use. The goal of this experiment is to measure biological effects of accelerated carbon ions in different cell lines with different radiosensitivity to photon radiation. Results will be used to determine the RBE of carbon ions for radiosensitive and radioresistant cells.

// Mirella Tanori 1 , Arianna Casciati 1 , Francesco Berardinelli 2 , Simona Leonardi 1 , Emanuela Pasquali 1 , Francesca Antonelli 1 , Barbara Tanno 1 , Paola Giardullo 2,3 , Alessandro Pannicelli 4 , Gabriele Babini 5 , Ilaria De Stefano 3 , Antonella Sgura 2 , Mariateresa Mancuso 1 , Anna Saran 1 and Simonetta Pazzaglia 1 1 Laboratory of Biomedical Technologies, Agenzia Nazionale per le Nuove Tecnologie, l’Energia e lo Sviluppo Economico Sostenibile (ENEA), CR-Casaccia, Rome, Italy 2 Department of Science, University Roma Tre, Rome, Italy 3 Department of Radiation Physics, Universita degli Studi Guglielmo Marconi, Rome, Italy 4 Technical Unit of Energetic Efficiency, ENEA, Rome, Italy 5 Department of Physics, University of Pavia, Pavia, Italy Correspondence to: Simonetta Pazzaglia, email: // Keywords : cerebellum, expression profiles, medulloblastoma, apoptosis, senescence Received : June 14, 2016 Accepted : June 26, 2016 Published : July 07, 2016 Abstract Mutations in DNA repair pathways are frequent in human cancers. Hence, gaining insights into the interaction of DNA repair genes is key to development of novel tumor-specific treatment strategies. In this study, we tested the functional relationship in development and oncogenesis between the homologous recombination (HR) factor Rad54 and Parp-1 , a nuclear enzyme that plays a multifunctional role in DNA damage signaling and repair. We introduced single or combined Rad54 and Parp-1 inactivating germline mutations in Ptc1 heterozygous mice, a well-characterized model of medulloblastoma, the most common malignant pediatric brain tumor. Our study reveals that combined inactivation of Rad54 and Parp-1 causes a marked growth delay culminating in perinatallethality, providing for the first time evidence of synthetic lethal interactions between Rad54 and Parp-1 in vivo . Although the double mutation hampered investigation of Rad54 and Parp-1 interactions in cerebellum tumorigenesis, insights were gained by showing accumulation of endogenous DNA damage and increased apoptotic rate in granule cell precursors (GCPs). A network-based approach to detect differential expression of DNA repair genes in the cerebellum revealed perturbation of p53 signaling in Rad54 -/- / Parp-1 -/- / Ptc1 +/- , and MEFs from combined Rad54/Parp-1 mutants showed p53/p21-dependent typical senescent features. These findings help elucidate the genetic interplay between Rad54 and Parp-1 by suggesting that p53/p21-mediated apoptosis and/or senescence may be involved in synthetic lethal interactions occurring during development and inhibition of tumor growth.

[Recensione]

The spatial distribution of radiation-induced DNA breaks within the cell nucleus depends on radiation quality in terms of energy deposition pattern. It is generally assumed that the higher the radiation linear energy transfer (LET), the greater the DNA damage complexity. Using a combined experimental and theoretical approach, we examined the phosphorylation-dephosphorylation kinetics of radiation-induced γ-H2AX foci, size distribution and 3D focus morphology, and the relationship between DNA damage and cellular end points (i.e., cell killing and lethal mutations) after exposure to gamma rays, protons, carbon ions and alpha particles. Our results showed that the maximum number of foci are reached 30 min postirradiation for all radiation types. However, the number of foci after 0.5 Gy of each radiation type was different with gamma rays, protons, carbon ions and alpha particles inducing 12.64 ± 0.25, 10.11 ± 0.40, 8.84 ± 0.56 and 4.80 ± 0.35 foci, respectively, which indicated a clear influence of the track structure and fluence on the numbers of foci induced after a dose of 0.5 Gy for each radiation type. The γ-H2AX foci persistence was also dependent on radiation quality, i.e., the higher the LET, the longer the foci persisted in the cell nucleus. The γ-H2AX time course was compared with cell killing and lethal mutation and the results highlighted a correlation between cellular end points and the duration of γ-H2AX foci persistence. A model was developed to evaluate the probability that multiple DSBs reside in the same gamma-ray focus and such probability was found to be negligible for doses lower than 1 Gy. Our model provides evidence that the DSBs inside complex foci, such as those induced by alpha particles, are not processed independently or with the same time constant. The combination of experimental, theoretical and simulation data supports the hypothesis of an interdependent processing of closely associated DSBs, possibly associated with a diminished correct repair capability, which affects cell killing and lethal mutation.